1. Field of the Invention
The present invention relates to a handler, and more particularly, to a transfer device of a handler for testing semiconductor device in which a pitch of each head of picker heads for absorbing and transferring semiconductors may be adjusted easily and variously.
2. Discussion of the Related Art
Generally, Module ICs including memory or non-memory semiconductors on one substrate circuitously and appropriately are released after various steps when manufactured. A handler is a device which automatically transfers the Module ICs such as semiconductors to a process and then tests them.
Commonly, after a handler re-installs semiconductors, contained in each user tray of a loading part, in a test tray using a transfer device, a handler transfers the test trays to a test site and then performs a testing. In succession, the handler re-contains the tested semiconductors in user trays of an unloading part according to the test results.
However, since pitches between each semiconductor lining up in the user tray are different from pitches between each semiconductor lining up in the test tray, pitches between each head of the picker heads should be varied.
That is, in a transfer device, the pitches between each picker head should be varied each into the pitches between each semiconductor in the user tray and/or the pitches between each semiconductor in the test tray.
The applicant of the present invention developed a transfer device capable of precisely and rapidly adjusting distances of picker heads in a simple structure without using a complex link. In Korea Patent First Publication 10-0248704 (date of publication: Mar. 15, 2000) is disclosed a device for adjusting each semiconductor pitch of a semiconductor tester wherein a cam shaft or a cam plate having a plurality of cam grooves formed inclined therein is installed and some part of each picker head is relative-movably connected to each cam groove of the cam shaft or the cam plate. In the device for adjusting each semiconductor pitch, when rotating the cam shaft by using a rotatory cylinder or rectilinearly moving the cam plate by a pneumatic cylinder, each picker head relatively moves along each cam groove of the cam shaft, thereby adjusting the pitch between each picker head performed.
More specifically, in the device for adjusting each semiconductor pitch there are two pitch adjusting steps. In a first step, when an end of a picker head is located at a first end of a cam shaft or a cam groove of a cam plate, the pitch between each picker head is minimized. In a second step, when a cam shaft is rotated by a rotatory cylinder or a pneumatic cylinder, or a cam plate rectilinearly moves and then an end of a picker head moves into a second end of a cam groove, the pitch between each picker head is maximized
However, since a conventional device for adjusting each semiconductor pitch includes only two steps of the maximum distance and the minimum distance for adjusting the pitch between each picker head, the cam shaft or the cam plate should be replaced to the ones corresponding with each semiconductor in case that the kinds and sizes of the semiconductors are varied.
In other words, when the kinds or the sizes of the semiconductors to be tested are varied, the pitches between the semiconductors in the user trays and the test trays are also varied. Thus, in case that the cam shaft or the cam plate is not replaced with the one suitable for the semiconductors, pitches between the semiconductors in the user tray and the semiconductors in the test tray do not accord with the pitches between the picker heads, thereby the test not being performed.
As a result, conventionally whenever the kinds and/or the sizes of the semiconductors to be tested are varied, the cam shaft or the cam plate is replaced with the one suitable for the semiconductors. Therefore, the replacing process is so complex and difficult that it takes much time and may cause a problem of deteriorating work efficiency and productivity.